WO2004092293A1

WO2004092293A1 - Adherent converted sheet

Info

Publication number: WO2004092293A1
Application number: PCT/JP2003/012994
Authority: WO
Inventors: Tamio Shikano; Katsukuni Nitta; Koichi Ishida
Original assignee: Yupo Corporation
Priority date: 2003-04-10
Filing date: 2003-10-09
Publication date: 2004-10-28
Also published as: CN1764706A; US20060051551A1; AU2003272966A1; US7338693B2; CN100352876C

Abstract

An adherent converted sheet easily stickable without involving swelling caused by taking in air, inexpensive, easily re-stickable, and superior in applicability. An adherent converted sheet characterized by comprising a sheet base material (A), and an adhesive layer (B) having a number of small recesses (b1) and projections (b2).

Description

Technical Fields

The present invention relates to an adhesive sheet used for a sticker, a label, and the like.

A conventional pressure-sensitive adhesive sheet is composed of a pressure-sensitive adhesive sheet formed by providing a pressure-sensitive adhesive layer flat on a sheet substrate, and a release sheet bonded to the flat pressure-sensitive adhesive layer. The release-treated surface of the release sheet is usually flat, and the release sheet is peeled off, and the pressure-sensitive adhesive layer surface of the pressure-sensitive adhesive sheet is attached to an adherend for use.

Such an adhesive-processed sheet often entraps air between the adhesive-processed sheet and the adherend, causing air pockets to become blisters, resulting in a projection on the surface of the adhered adhesive-processed sheet. However, there was a problem that the appearance was significantly impaired. This problem was remarkable especially when the area of the adhesive sheet was large or when the surface of the adherend was smooth.

Also, when the adherend was made of plastic (polycarbonate, acrylic, foamed polystyrene resin, etc.), gas was generated from the plastic surface over time, and blisters were sometimes generated on the adhesive sheet.

In order to solve the above-mentioned problems, various types of adhesive processing have been described in the specification of Utility Model Registration No. 2503371, Japanese Patent Publication No. A seat has been proposed. However, these φ technologies had lower productivity and higher cost than ordinary adhesive sheets.

Therefore, an object of the present invention is to solve the above-mentioned problem and provide an inexpensive pressure-sensitive adhesive sheet which is free from blistering at the time of sticking or after sticking, is excellent in productivity, and is inexpensive. <Disclosure of Invention>

The present inventors have conducted intensive research to solve the above-described problems, and as a result, have found that

A and a pressure-sensitive adhesive sheet characterized by comprising a pressure-sensitive adhesive layer B having a large number of small depressions b1 and a large number of small protrusions b2, the production cost is low, and The present inventors have found that since blisters do not occur at the time of sticking to the body, the workability is greatly improved without impairing the appearance of the pressure-sensitive adhesive sheet, and the present invention has been completed.

That is, the present invention provides a pressure-sensitive adhesive sheet characterized by containing a sheet substrate, a pressure-sensitive adhesive layer B having a large number of small depressions b1 and a large number of small protrusions b2.

In a preferred embodiment of the pressure-sensitive adhesive sheet of the present invention, a sheet substrate A, a pressure-sensitive adhesive layer B having a large number of small depressions b1 and a large number of small projections b2, a large number of ridges c1 and a large number of It is preferable to use a release sheet C having a perforated structure c2. The pressure-sensitive adhesive layer B has a basic flat surface on the side in contact with the release sheet C, the small depression b1 is depressed from this basic flat surface, and the small protrusion b2 is from this basic flat surface. It is preferable that they protrude. The small depression b 1 is recessed from the basic flat surface at a depth of 1 m to the thickness of the adhesive layer B, and the small protrusion b 2 is 1 to 150 m from the basic flat surface. It is preferable that it protrudes.

In addition, the cross-sectional shape of the small depression b1 in a plane parallel to the basic flat surface is at least one selected from the group consisting of a circle, an ellipse, a donut, a crescent, and an η polygon (η is a natural number of 3 or more). Preferably, the shape is at least one shape, more preferably at least one shape selected from a donut shape and a crescent shape. Similarly, the cross-sectional shape of the small protrusion b 2 in a plane parallel to the basic flat surface is selected from the group consisting of a circle, an ellipse, a donut, a crescent, a gourd, and an ellipse (n is a natural number of 3 or more). And preferably at least one shape, more preferably at least one shape selected from the group consisting of a donut shape, a crescent shape and a sunflower shape. It is particularly preferred that the shape is formed adjacent to and along the base contour on the one basic flat surface.

Small depressions b 1 are separated from each other on the basic flat surface and are scattered. Is preferred. It is preferable that the small depressions b1 are distributed at a frequency of 10 to 100, 000 / cm ² . Further, it is preferable that the small protrusions b2 are separated from each other and scattered on the basic flat surface. The small protrusion b 2 is 10 to 10,. . . Pieces . ! !! It is preferable that they are distributed at a frequency of ² .

Further, the width of the base of the small protrusion b2 on the basic flat surface is preferably 1 to 1,500 m.

The thickness of the protruding portion c1 of the release sheet C is preferably 1 // m or more thicker than the thickness of the non-perforated portion of the release sheet C. Further, the release sheet C is preferably made of a thermoplastic resin.

FIG. 1 is an example of a cross-sectional view of the basic configuration of the pressure-sensitive adhesive sheet of the present invention. FIG. 2 is a schematic view of the pressure-sensitive adhesive sheet viewed from a vertical direction (overlook) on the pressure-sensitive adhesive layer B side.

FIG. 3 is an example of a cross-sectional view of another basic configuration of the pressure-sensitive adhesive sheet of the present invention. FIG. 4 is a schematic view of the pressure-sensitive adhesive sheet viewed from a vertical direction (overlook) on the pressure-sensitive adhesive layer B side.

In the figure, 1 is a sheet substrate, 2 is an adhesive layer B, 3 is a small dent b1, 4 is a small protrusion b2, and 5 is a basic flat surface.

By providing the raised portion c1 and the perforated structure c2 on the release sheet C, the shape of the release sheet C is transferred to the adhesive layer B during the adhesive processing, and the adhesive layer B has a corresponding number of small depressions. The portion b1 and the small protrusion b2 can be formed.

By having such small recesses b1 and small projections b2, when the adhesive sheet is lightly attached to the adherend, the small projections b2 of the adhesive layer B first adhere to the adherend. However, there is a gap between the basic flat surface of the pressure-sensitive adhesive layer B and the surface of the adherend that communicates with the outside. As a result, most of the air between the pressure-sensitive adhesive sheet and the adherend can be evacuated to the outside via the gap that communicates with the outside, and large uneven blisters do not occur at the time of sticking. In addition, since the small amount of air remaining between the pressure-sensitive adhesive sheet and the adherend accumulates in the small depression b1, the construction can be performed without deteriorating the appearance.

The pressure-sensitive adhesive layer B has a basic flat surface, so that the pressure-sensitive adhesive sheet When the adhesive layer B is strongly pressed to the adherend, the basic flat surface of the adhesive layer B is continuously adhered to the adherend, and the gap communicating between the adhesive layer B and the adherend is eliminated. However, strong adhesive strength can be obtained. In addition, even during strong pressure bonding, the small depression b1 is not adhered to the adherend, and the gas generated with the lapse of time when the adherend is plastic is uniformly accumulated in the small depression bl. However, even after the construction, no large uneven blisters are generated and the appearance is not significantly impaired.

Furthermore, when the pressure-sensitive adhesive sheet is lightly stuck to the adherend, the small protrusions b2 of the pressure-sensitive adhesive layer B first come into close contact with the adherend, so that the contact area is small. For this reason, when re-attaching, it is easy to peel off and re-attach. Also, it is possible to suppress a decrease in adhesive strength due to peeling.

Due to the above advantages, for example, when the pressure-sensitive adhesive sheet of the present invention is applied as a large-sized label, positioning and the like are easy, work is not required, work is completed in a short time, and a beautiful finish is obtained. It becomes possible. <Brief description of drawings>

FIG. 1 is an example of a cross-sectional view of the basic structure of the pressure-sensitive adhesive sheet of the present invention. FIG. 2 is a schematic diagram of the pressure-sensitive adhesive sheet of FIG. 1 as viewed from the vertical direction (overhead view) on the pressure-sensitive adhesive layer B side.

FIG. 3 is an example of a cross-sectional view of the basic configuration of the pressure-sensitive adhesive sheet of the present invention. FIG. 4 is a schematic diagram of the pressure-sensitive adhesive sheet of FIG. 3 as viewed from the vertical direction (overhead view) on the pressure-sensitive adhesive layer B side.

The symbols in the figure are as follows.

1: Sheet base material A

2: Adhesive layer B

3: Small recess b 1

4: Small protrusion b 2

5: Basic flat surface <Best mode for carrying out the invention>.

(Sheet substrate A)

The material of the sheet substrate A is not particularly limited, and various substrates such as natural paper, plastic film, synthetic paper, woven fabric, and nonwoven fabric can be used. In particular, a plastic film such as polyolefin or polyester, or a synthetic paper composed of polyolefin or polyester is basically a poorly air-permeable base material, so that the technique of the present invention can be preferably applied. In addition, these base sheets are preferable because the base material is strong and the sheet base material is not broken at the time of peeling and can be peeled cleanly.

The thickness of the sheet substrate A is from 30 to 200 μm, preferably from 40 to L500 μπι.

(Release sheet C)

Examples of the material of the release sheet C include thermoplastic resin sheets such as a polyolefin resin such as polyethylene and polypropylene, a polyester resin such as polyethylene terephthalate, a polyamide resin such as nylon, and a thermoplastic resin such as these. Examples include laminated paper in which a sheet is laminated on one or both sides of natural paper, metal foil, and a composite of metal foil and thermoplastic resin sheet, or a combination of metal foil and natural paper. Preferably, it is a thermoplastic resin sheet, and more preferably, it is a polypropylene film.

The release sheet C is subjected to a perforation process to be described later in order to provide a raised portion c1 and a perforated structure c2. The surface on the peeling surface side before the perforation process forms the basic flat surface of the pressure-sensitive adhesive layer 後に later, and is preferably smooth, but may be rough for the purpose of controlling the peeling performance. It is.

Before applying the release agent on the release sheet C, the surface of the release sheet C may be subjected to a surface treatment such as corona discharge, frame treatment, and ozone treatment.

Examples of the release agent include a silicone resin, a fluororesin, an aminoalkyd resin, a polyester resin and the like, and a silicone resin is preferable. These are used as emulsion, solvent or solventless types.

The thickness of the release sheet C of the present invention is determined from the viewpoints of handling strength, ease of perforation, etc. 1150 μΐη is preferred, and more preferably 10〜13 μΟη.

(Punching process)

The perforated peripheral portion of the release sheet C of the present invention is rolled up in the thickness direction of the sheet by being thermally or plastically deformed by a perforation method described later, and the thickness of the non-perforated portion of the sheet (or (The average thickness of the sheet before the perforation process). In the present invention, the portion where the thickness is increased by the perforation processing on the release sheet C is referred to as a raised portion c1. The thickness of the protruding portion c1 is preferably at least 1 / m thicker than the thickness of the non-perforated portion of the release sheet C (or the average thickness of the release sheet before the perforation process). It is more preferable that the thickness is increased by the thickness of ηι to the pressure-sensitive adhesive layer B, and it is particularly preferable that the thickness is increased by the thickness of 3 μπι to the thickness of the pressure-sensitive adhesive layer Β.

If the thickness of the raised portion c 1 is less than 1 / m compared to the thickness of the non-perforated portion, the release sheet C cannot have a sufficient protrusion height, and the pressure-sensitive adhesive layer will The depression depth of the small depression b formed in B cannot be obtained, and the blister prevention, which is the purpose of the present invention, cannot be achieved.

In the release sheet C, a perforated structure c2 is generated by the perforation process. The perforated structure c 2 may be a through hole or a semi-through hole (a hole that does not penetrate in the thickness direction of the release sheet). Further, the perforated structure c2 of the release sheet C may have a shape and a hole diameter which change in the thickness direction as long as the constitutional requirements of the present invention are satisfied. The release sheet C may be one in which a through-hole is provided by a perforation process, another substrate is laminated, and one side of the through-hole is closed to make the perforated structure c 2 a semi-through-hole.

The depth of the perforated structure c2 is not particularly limited as long as the performance can satisfy the constituent requirements of the present invention. Above all, it preferably has a depth of 1 m or more from the surface of the release sheet C, more preferably 1 jum to the depth of the thickness of the release sheet C, and more preferably 3 μπι to the release sheet. It is particularly preferable to have a depth in the range of the thickness of C.

The hole diameter of the perforated structure c2 is also not particularly limited as long as it can have the performance satisfying the constituent requirements of the present invention. Specific examples are 5 to 2, Ο Ο Ο μ πι, preferably 50 1,500 μm, which can be formed by the following perforation processing method. The thickness (height) of the protruding portion c1 and the depth of the perforated structure c2 were determined by cutting out the cross section of the peeled sheet C after perforation with a microtome, ion-etching with a commercially available ion coater, and depositing gold. It was calculated from the cross-sectional morphology using a scanning electron microscope (trade name: S-300 ON, manufactured by Hitachi High-Technologies Corporation).

The punching method for providing the raised portion c1 and the perforated structure c2 on the release sheet C was selected from a hot needle perforation method, a laser beam perforation method, an electron beam irradiation perforation method, a plasma perforation method, and a high pressure discharge perforation method. At least one method can be applied, and it can be appropriately selected and combined according to the material, thickness, processing speed, and perforation diameter of the release sheet C.

(Adhesive layer B)

The kind (material) and thickness (coating amount) of the pressure-sensitive adhesive layer B of the present invention depends on the material and thickness of the base material used for the sheet base material A and the environment (material and condition of the adherend, Various choices are possible depending on the indoor or outdoor environment, temperature, humidity, period of use, etc., and the desired adhesive strength, and are not particularly limited.

As an example of the pressure-sensitive adhesive layer B, a commonly used water-based or solvent-based pressure-sensitive adhesive can be applied and dried. Types (materials) can be natural rubber, synthetic rubber, acrylonitrile, urethane, EVA, silicone, etc. These polymer adhesives can be organic, solvent solutions, emulsion dispersers, etc. It can be used in the form of a dispersion in an aqueous solution such as dijon.

(Coating method)

There are two methods of providing the adhesive layer B on the sheet substrate A: direct coating, in which the adhesive is applied directly to the sheet substrate A, and indirect coating, in which the adhesive is applied to the release sheet C once. However, the technology of the present invention is applicable to both, and there is no particular limitation.

The method for applying the pressure-sensitive adhesive is not particularly limited. For example, comma-coat coating, reverse-coat coating, gravure-coat coating, kiss-coat coating, knife-coat coating, bar-coat coating, curtain-coat coating, and adhesives coated with these methods on process paper And a transfer method for transferring. As the thickness (coating amount), it is generally used in a dry weight of 0.5 SAOO g / m ² , or in a range of 0.5 to 400 μm in dry thickness.

(Method of forming small recesses b1 and small protrusions b2)

The small depression b1 and the small protrusion b2 provided in the pressure-sensitive adhesive layer B can be formed by using the perforated release sheet C when the pressure-sensitive adhesive layer B and the release sheet C are laminated (indirect coating). In the case of (1), when the pressure-sensitive adhesive is applied to the release sheet C), the ridges c1 of the release sheet C bite into the basic flat surface of the pressure-sensitive adhesive layer B to form the corresponding small depressions b1. At the same time, the pressure-sensitive adhesive flows into the perforated structure c2 of the release sheet C from the basic flat surface of the pressure-sensitive adhesive layer B to form the corresponding small projections b2. These small depressions b1 correspond to the protrusions c1, and the small protrusions b2 correspond to the perforated structure c2.

In addition, in the case of direct coating in which the pressure-sensitive adhesive layer B is directly provided on the sheet base material A, when the release sheet C is laminated, the raised portion c1 of the release sheet C is formed on the basic flat surface of the pressure-sensitive adhesive layer B. The extruded adhesive is formed around the small depression bl as a small protrusion b2 like a dike at the same time as the corresponding small depression b1 is formed by biting into the hole. In this case, the small depression b1 that occurs corresponds to the protrusion c1, but the small projection b2 does not necessarily correspond to the perforated structure c2.

The depression depth of the small depression b 1 is preferably in the range of 1 μm from the basic flat surface of the adhesive layer B to the thickness of the adhesive layer B, and 3 μππ to the adhesive layer from the basic flat surface. It is more preferable that the thickness be within the range of B. If the depth of the small depression b 1 is less than 1 m, the small depression b 1 also easily adheres to the adherend, and the residual fine air or gas generated from the adherend is unevenly accumulated, resulting in a small result. Undesirably, blisters are generated and the appearance is significantly impaired.

The protrusion height of the small protrusion b2 is preferably in the range of 1 / zm to 150m from the basic flat surface of the adhesive layer B, and in the range of 3m to 100m from the basic flat surface. It is more preferable that If the height of the small projections b2 is less than 1 m, the gap between the pressure-sensitive adhesive layer B and the adherend communicating with the outside will be small when the pressure-sensitive adhesive sheet is adhered to the adherend, and air will escape. It worsens, resulting in large and uneven blisters, and the appearance is remarkably impaired. If it is larger than 150 μm, attach it to the adherend. Even if pressure is applied strongly after bonding, the basic flat surface cannot contact the surface to be adhered, and it is disadvantageous when a strong adhesive force is required.

The depression depth of the small depression b1 and the protrusion height of the small protrusion b2 are adjusted by adjusting the pressure-sensitive adhesive sheet after processing to a temperature equal to or lower than the glass transition point of the pressure-sensitive adhesive. After cutting out and ion-etching and gold vapor deposition with a commercially available ion coater, it was calculated from the cross-sectional morphology using a scanning electron microscope (trade name: S-30000N, manufactured by Hitachi High-Technologies Corporation).

The shape of the small depression b1 is essentially a transfer of the shape of the protrusion c1 of the release sheet C, and is not particularly limited, but is parallel to the basic flat surface of the adhesive layer B. At least one shape selected from the group consisting of circular, elliptical, donut, crescent, and n-gonal (n is a natural number of 3 or more) is preferred. The shape is preferably at least one shape selected from any of the shapes.

The above-mentioned shape is a suitable shape that can be selected in the perforating process on the release sheet C according to the present invention, and the donut shape and the crescent shape are particularly preferable because they can be formed by an inexpensive processing process.

Similarly, the cross-sectional shape of the basic small protrusion b 2 in a plane parallel to the basic flat surface is selected from the group consisting of a circle, an ellipse, a donut, a crescent, a gourd, and an ellipse (n is a natural number of 3 or more). At least one shape selected from the group consisting of a donut shape, a crescent shape, and a gourd shape, and more preferably at least one shape selected from the group consisting of a doughnut shape, a crescent shape, and a gourd shape. It is particularly preferable that the shape be formed along the contour at the base of the flat surface and adjacent to the outer periphery thereof.

By providing the above-mentioned shape, even if minute blisters are generated, they are not conspicuous and do not significantly impair the appearance.

According to the technology of the present invention, the small depression b1 and the small projection b2 may be independently and separately provided, but the small projection b2 is formed adjacent to the small depression b1. In this case, the small air remaining between the adhesive layer B and the adherend or the gas generated from the adherend concentrates on the small recess b1 adjacent to the small protrusion b2 Captured and uneven Swelling can be effectively suppressed.

Many small depressions b1 exist on the basic flat surface, and they are preferably separated from each other and scattered. When the small recesses b1 are densely present, the ratio of the basic flat surface decreases, and the adhesive strength of the pressure-sensitive adhesive base sheet decreases only in that portion. If it is sparse, there is a danger that blisters may be generated due to the inability to capture the minute air or gas between the adhesive layer B and the adherend.

Small recess bl is preferably distributed in 1 0-1 0, 0 0 0 / cm ² of frequency, 1 5-5, that are distributed at a frequency of 0 0 0 / cm ² But more preferred.

Since the small depression b1 of the pressure-sensitive adhesive layer B is formed corresponding to the projection c1 of the release sheet C, the projection c1 of the release sheet C is the same as the small depression b1. It is similarly distributed by frequency.

If the distribution frequency of the small depressions b1 is less than 10 cm ^2, it is not preferable because the blister prevention effect is reduced. If it exceeds 10 000 / cm ² , the required adhesive strength cannot be obtained, which is not preferable.

It is particularly preferable that the small depressions b1 are evenly distributed on the basic flat surface from the viewpoint of preventing blisters.

Similarly, a large number of small protrusions b2 are present on the basic flat surface, and they are preferably separated from each other and scattered. If the small protrusions b2 are densely located, the contact area with the adherend is reduced, and sufficient adhesive strength cannot be obtained even when pressure is applied strongly. If the adhesive sheet is adhered to the adherend when it is sparse, the gap between the adhesive layer B and the adherend that communicates with the outside will be small, so that air will not escape easily, resulting in a large gap. Uneven blisters may occur.

Small protrusions b 2 are preferably distributed in 1 0-1 0, 0 0 0 / cm ² of frequency, 1 5-5, are distributed at a frequency of 0 0 0 / cm ² Is better.

The perforated structure c2 of the release sheet C has a frequency substantially similar to that of the small protrusions b2 of the pressure-sensitive adhesive layer B and is similarly distributed. Significantly impair undesirably greatly uneven blister occurs appearance when the distribution frequency of the small projections b 2 is less than 1 0 / cm ^2. If it exceeds 10 000 / cm ² , the required adhesive strength cannot be obtained, which is not preferable.

The distribution frequency of the small protrusions b2 on the basic flat surface may be uniform or non-uniform as long as it is within the above range. If it is uniform, the entire surface of the sheet can be given an even adhesive force, improving workability. If it is not uniform, it is possible to create a label or the like with partially weakened adhesive strength, and it can be applied to labels with coupons and the like. Regarding the size of the small protrusion b2, the maximum width of the base portion on the basic flat surface is preferably 1 to 1,500 / im, more preferably 3 to 1,00xm. If the maximum width of the small protrusion b2 is less than 1 m, it is not preferable because the minute air or gas between the pressure-sensitive adhesive layer B and the adherend cannot be taken in and blisters are generated. If the width of the small protrusion b2 is larger than 1,500 μιη, the area ratio occupied by the basic flat surface decreases, and the required adhesive strength cannot be obtained.

The sheet substrate of the pressure-sensitive adhesive sheet of the present invention can be decorated by various printing methods. Printing methods include electrophotographic, melt thermal transfer, sublimation thermal transfer, rewritable marking, and inkjet printers, as well as letterpress printing, gravure printing, flexographic printing, solvent-based offset printing, and ultraviolet light. Various printing methods such as curable offset printing and screen printing are applicable. Examples>

Hereinafter, the present invention will be described specifically with reference to Examples, Comparative Examples, and Test Examples. The materials, amounts used, ratios, treatment details, treatment procedures, and the like shown in the following examples can be appropriately changed without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be construed as being limited by the specific examples described below.

[Example 1]

60 m thick polypropylene film (trade name: Pyrene P2761, Toyo Spinning Co., Ltd.) was subjected to a through-hole perforation process using a hot needle perforation method, and the rolled surface of the perforated portion was subjected to silicone treatment to obtain a release sheet C. Pore size 400 m _s number of holes is 60 Bruno cm ^2, the depth of the perforated part is 1 20 _mu m, the height of the raised portion c 1 that occurred on the periphery of the perforated portion was 60 / im .

Next, a synthetic paper (trade name: SGS-80, manufactured by Upo Corporation) with a thickness of 80 μΐη was used as the sheet substrate A, and a solvent-based acryl-based pressure-sensitive adhesive was used as the adhesive layer (trade name: Oripine BPS) 1 109, Toyo Ink Chemical Industry Co., Ltd.) was applied with a comma coater so that the coating amount after drying was 30 gZm ^2, and dried to obtain an adhesive sheet (sheet base material A + The adhesive layer was designated as B).

The pressure-sensitive adhesive sheet was laminated so that the surface of the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet was in contact with the silicone-coated surface of the release sheet C, to obtain a pressure-sensitive adhesive sheet. Table 1 shows the physical properties of the obtained pressure-sensitive adhesive sheet.

[Example 2]

Peel off the release paper of a commercially available adhesive-coated sheet with a thickness of 190 m (trade name: XJP-190, manufactured by UPPO Corporation), and obtain the adhesive layer surface of this adhesive-coated sheet and Example 1. The release sheet C was laminated so that the silicon-treated surface of the release sheet C was in contact with the release sheet C to obtain an adhesive sheet. Table 1 shows the physical properties of the obtained pressure-sensitive adhesive sheet. [Example 3]

After drying a solvent-based acrylic pressure-sensitive adhesive (trade name: Olivein BP S1109, manufactured by Toyo Ink Chemical Industry Co., Ltd.) as pressure-sensitive adhesive layer B on the silicone-treated surface of release sheet C obtained in Example 1, Was coated with a bar coater so that the coating amount was 30 μιη, and dried to obtain a laminate (adhesive layer Β + release sheet C).

Next, an 80 / xm-thick synthetic paper (trade name: SGS-80, manufactured by Topo Corporation) is laminated as the sheet base material 剤 with the adhesive layer B of the laminate to form an adhesive sheet. I got it. Table 1 shows the physical properties of the obtained pressure-sensitive adhesive sheet.

Throughout Examples 1 to 3, the materials used (sheet base material, adhesive, release sheet) Are generally available to those skilled in the art, and no special processing equipment or processing conditions are used except for pre-perforating the release sheet. Therefore, unlike the currently proposed technology, a special member (processing step) is required, production is inferior, cost is not increased, and an adhesive processing sheet that can solve the problem can be obtained at low cost. Was.

[Comparative Example 1]

A 60〃 m-thick polypropylene film (trade name: Pyrene P2761, manufactured by Toyobo Co., Ltd.) was treated with silicone to obtain a release sheet C. The same operation as in Example 1 was performed except that the through-hole punching treatment was not performed, and an adhesive processed sheet was obtained. Table 1 shows the physical properties of the obtained pressure-sensitive adhesive sheet.

(Test example)

(Small depression b 1 Depression depth, Small protrusion b 2 Projection height)

In each of the examples and comparative examples, the depression depth of the small depression b1 and the projection height of the small projection b2 formed on the pressure-sensitive adhesive layer B were calculated by the above-described method.

(Workability)

Peel off the release sheet C of the pressure-sensitive adhesive sheet of each example and comparative example, lightly affix it to a transparent and highly smooth glass plate, and then peel it off again. Judgment was made based on the following criteria.

〇: Easy to peel, no wrinkles or adhesive residue.

X: There is resistance during peeling, and wrinkles and adhesive residue are generated.

(Prevent swelling)

After peeling off the release sheet c of the pressure-sensitive adhesive sheet of each example and comparative example, lightly affixing it to a transparent and smooth glass plate, and visually inspecting for blisters when crimping by hand using a valen Was determined according to the following criteria.

〇: No blistering is observed.

X: Large and uneven blisters are generated. Table 1 shows the evaluation and judgment results for each test example. Table 1

Although the present invention has been described in detail and with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention.

This application is based on Japanese Patent Application (No. 2003-106356) filed on April 10, 2003, the contents of which are incorporated herein by reference.

As is clear from Table 1, the use of the pressure-sensitive adhesive sheet of the present invention makes it easy to re-paste and does not generate large and uneven blisters during and after sheet construction. It can be used effectively for signs, namers, tack sheets, etc.

Claims

The scope of the claims

1. A pressure-sensitive adhesive sheet comprising a sheet base material and a pressure-sensitive adhesive layer B having a large number of small depressions b1 and a large number of small protrusions b2.

2. The pressure-sensitive adhesive sheet according to claim 1, further comprising a release sheet C having a number of raised portions c1 and a number of perforated structures c2.

3. The surface of the pressure-sensitive adhesive layer B that comes into contact with the release sheet C has a basic flat surface, the small depression b1 is depressed from the basic flat surface, and the small protrusion b2 protrudes from the basic flat surface. 3. The pressure-sensitive adhesive sheet according to claim 2, wherein:

4. The depth of the small depression b1 is in the range of 1 μm from the basic flat surface of the adhesive layer B to the thickness of the adhesive layer B, and the height of the small protrusion b2 is 4. The pressure-sensitive adhesive sheet according to claim 1, wherein the pressure is in a range of 1 μΐη to 150 μπι from the basic flat surface of the layer B.

5. The cross-sectional shape of the small depression b1 in a plane parallel to the basic flat surface is at least one selected from the group consisting of a circle, an ellipse, a donut, a crescent, and an n-gon (n is a natural number of 3 or more). The cross-sectional shape of the small projection b2 in a plane parallel to the basic flat surface is at least one of a circle, an ellipse, a donut, a crescent, a hyotan, an n-square (n is 3 or more) The pressure-sensitive adhesive sheet according to any one of claims 1 to 4, wherein the pressure-sensitive adhesive sheet has at least one shape selected from the group consisting of (natural numbers).

6. The cross-sectional shape of the small depression b1 in a plane parallel to the basic flat surface is at least one shape selected from a donut shape and a crescent shape, and in a surface parallel to the basic flat surface. The cross-sectional shape of the small protrusion b 2 is a donut shape, a crescent shape, 5. The pressure-sensitive adhesive sheet according to any one of claims 1 to 4, wherein the pressure-sensitive adhesive sheet has at least one shape selected from the group consisting of a rhombus shape.

7. The cross-sectional shape of the small depression b1 in a plane parallel to the basic flat surface is at least one shape selected from a donut shape and a crescent shape, and the small protrusion b2 is small. 5. The pressure-sensitive adhesive sheet according to claim 1, wherein the depression b1 is formed adjacent to the base flat surface along the basic flat surface.

8. The pressure-sensitive adhesive sheet according to any one of claims 1 to 7, wherein the small depressions b1 are separated from each other on the basic flat surface and are scattered.

9. The pressure-sensitive adhesive sheet according to any one of claims 1 to 8, wherein the small protrusions b2 are separated from each other on the basic flat surface and are scattered.

1 0. Small depressions bl are distributed at a frequency of 10 to 100,000 pieces / cm ² , and small projections b 2 are 10 to 100,000 pieces cm. of the base in the pressure-sensitive adhesive processing Sea _c 1 1. on the basic flat surface of the small protrusion b 2 according to any one of claims paragraph 1 to 9, wherein characterized that you have distributed in ^two frequency The maximum width is 1-1,

The pressure-sensitive adhesive sheet according to any one of claims 1 to 10, wherein the pressure-sensitive adhesive sheet has a length of 500 m.

1 2. When the adhesive sheet is used, the basic flat surface of the adhesive layer B and the adherend surface are in continuous contact, and there is no gap between the adhesive sheet and the adherend surface. The pressure-sensitive adhesive sheet according to any one of Items 1 to 11.

1 3. It has many raised parts c1 and many perforated structures c2. Release sheet c.

14. The release sheet C according to claim 13, wherein a number of raised portions c1 and a number of perforated structures c2 are formed by a perforation process.

15. The release sheet C according to claim 13 or 14, wherein the release sheet C is made of a thermoplastic resin.

16. The release sheet C according to any one of claims 13 to 15, wherein the thickness of the raised portion c1 is at least 厚い μπι thicker than the thickness of the non-perforated portion. .